Ignition system for gas lighters or the like



Feb. 11, 1969 H,D1ETERL E 3,427,117

IGNITION- SYSTEM FOR GAS LIGHTERS OR THE LIKE Filed Oct. 17, 1966 Ffg.1

BATTERY United States Patent Office 3,427,l 17 Patented Feb. 11, 1969 3,427,117 IGNITION SYSTEM FOR GAS LIGHTERS R THE LIKE Horst Dieterle, Frankfurt am Main, Germany, assignor to Heinrich Maltner, G.m.b.H., Offenbach am Main,

Germany Filed Oct. 17, 1966, Ser. No. 587,121 Claims priority, application Germany, Oct. 15, 1965,

M 66,947 U.S. Cl. 431-255 Int. Cl. F23q 3/01 16 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to improvements in ignition systems for gas lighters or the like. More particularly, the invetnion relates to an electrical ignition system of the type which can ignite a jet of gaseous fuel by causing a spark to jump across the gap defined by two electrodes which are connected to the high-voltage secondary circuit of a transformer.

In heretofore known gas lighters which utilize electrical ignition systems, the electrodes are connected with the secondary of the transformer by wire-like conductors. The electrodes are installed in a holder of insulating material which is mounted in the lighter housing independently of the transformer. As a rule, the electrical connection between the electrodes and the transformer is established after the transformer and the electrodes are installed in the lighter housing. This involves much work and the relatively small parts are hard to reach. Furthermore, presently known gas lighters which utilize electrical ignition systems occupy too much space because the mounting means for the transformer are independent of the holder or holders for the electrodes. Attempts to simplify the assembly of an electrically operated gas lighter by establishing an electrical connection between the electrodes and the transformer prior to installing such parts in the lighter housing have met with little success because the conductor wires are in the way when the electrode holder and the transformer are placed into and xed to the housing. Soldering of wires after the electrodes are installed in the housing is very difficult because the space available for introduction of a soldering iron is very small.

Accordingly, it is an important object of the present invention to provide a novel and improved electric ignition system for use in gas lighters and similar apparatus wherein a gaseous fuel is to be ignited by electric sparks, and to construct and assemble the ignition system in such a way that it can `be readily installed with little loss in time, by resorting to semiskilled or unskilled labor, and without the danger of damaging or interrupting the electrical connections between the electrodes and the transformer.

Another object of the invention is to provide a very compact electrical ignition system which can be readily accommodated in miniature lighters, which can be automatically retained by the housing of a lighter, and which can be installed without utilizing any special tools.

An additional object of the invention is to provide an ignition system which is protected from overheating when properly installed in a gas lighter or in another apparatus utilizing high-voltage sparks for ignition of fuel and whose components can be mass-produced of readily available materials.

Still another object of the invention is to provide an electrical ignition system which exhibits highly satisfactory resistance to mechanical stresses.

Briefly stated, one vfeature of my invention resides in the provision of an ignition system for gas lighters and analogous apparatus wherein a jet of fuel is ignited by an electric spark. The ignition system comprises a transformer having a high-voltage secondary circuit, a pair of electrodes defining lbetween themselves a spark gap which is adjacent to the path of fuel jets, an electrical connection between the high-tension leads of the secondary circuit and the electrodes, and holder means consisting of insulating material and supporting the two electrodes. The holder means is rigidly assembled with the transformer in such a way that the transformer supports the holder means (and hence the electrodes) or vice versa. The holder means may consist of a casting resin (for example, an epoxy resin) and its main body portion preferably surrounds at least a part of the transformer. Suitable coupling portions of the main body portion of the hol-der means may snap into a carrier provided in or constituted by the outer housing of the gas lighter to maintain the holder means and the transformer in requisite position.

The terminal portions of the electrodes are preferably surrounded by sheaths which are either embedded in or are made integral with the main vbody portion of the holder means. The latter may further comprise additional projections or protuberances, for example, one or more walls which are outwardly adjacent to the electrodes to `shield them kfrom the metallic parts of the lighter housing, one `or more ydistancing projections which determine the minimum distance lbetween the outer housing of the lighter and the windings of the transformer, a partition which extends between the sheaths for the electrodes, and a projection supporting the contact spring for the battery or another source of electrical energy which is to be connected with the primary winding of the transformer.

The novel features which are considered as characteristic of the invention are `set forth in particular in the appended claims. The improved ignition system itself, however, both as to its construction and its lmode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with re-ferenee to the accompanying drawings, in which:

FIG. l is a side elevational view of a gas lighter including an ignition system which embodies one form of my invention, a portion of the lighter and certain parts of the ignition system being broken away;

FIG. 2 is a top plan view of the lighter with the cover broken away and the insulating sheaths for the electrodes shown in section;

PIG. 3 is a front elevational view of a modified ignition system wherein the sheaths for the electrodes are integral with the main body portion of the holder means; and

FIG. 4 is a top plan view of a gas lighter which embodies a third ignition system, certain parts of the lighter and of the ignition system being shown in horizontal section.

Referring lirst to FIGS. 1 and 2, there is shown a gas lighter which comprises an outer housing or shell 1 accommodating an lnner housing or carrier 2 which supports the impro-ved ignition system and certain other lighter elements. The lighter further comprises a burner having a tube 3 which can discharge jets of vaporized liquid fuel. The means for opening the burner valve (not shown) includes a collar 4 at the upper end of the burner tube 3 and a lifter or shifter 5 which can move the collar 4 upwardly to thereby open the valve in a manner Well known from the art of gas lighters and not forming part of the present invention. The rate of fuel ow through the burner tube 3 is controllable by a wheel-shaped adjusting element 6 having a milled or knurled peripheral surface which extends from the outer housing 1.

The ignition system comprises two electrodes 7, 8 which define between themselves a spark gap sufficiently close to the path of fuel issuing from the tube 3 to insure the generation of a flame when a spark is produced between the exposed tips of the electrodes. High-voltage impulses are supplied by a transformer 9 whose secondary or highvoltage circuit is electrically connected with the electrodes 7 and 8, preferably by soldering. The flame produced on ignition of a fuel jet propagates itself outwardly through an opening 10 provided in the top panel of a cover 11 which is removably connected with the base part 12 of the outer housing 1. The actuating means for opening the burner valve and the means for completing the circuit of the ignition system are of well known design and form no part of the present invention; therefore, suchactuating and circuit completing means are not shown in the drawings. The base part 12 of the outer housing 1 further accommodates a reservoir for highly compressed liquefied fuel and certain other lighter elements, such as a battery, a capacitor, a switch and/ or others.

In accordance with my present invention, the transformer 9 can support the electrodes 7, 8 or vice versa in that the holder means 14 for the electrodes constitutes a frame or chassis for the transformer. This holder means comprises a substantially block-shaped main body portion which surrounds at least a portion of the transformer 10 and preferably consists of a casting resin with good insulating properties. The electrodes extend into the main body portion of the holder means 14 and are soldered, brazed or otherwise electrically connected Iwith the hightension leads of the secondary circuit as shown in FIG. l at 15. The main body portion of the holder means 14 comprises a projection or boss 16 which extends toward the burner tube 3 and through which the electrodes 7, 8 extend so that the structural unit including the electrodes and the transformer is rendered more rigid. The holder means 14 further includes two insulating sheaths 17, 18 which respectively surround the major parts of the electrodes 7, 8 and extend into the interior of the projection 16. It will be seen that the holder means 14 provides an electrical insulation for both electrodes all the way from the connections 15 and close to the actual spark gap.

The main body portion of the holder means 14 is provided with a plurality of additional projections 19, 20 constituting coupling portions which serve to connect it to the carrier 2. Such coupling portions 19, 20 are provided at the opposite sides of the transformer 10 and are received by snap action in complementary recesses or cutouts of the carrier 2. To this end, the carrier walls preferably consist of slightly elastic material so that they may be moved apart in order to allow for introduction of the holder means 14 so that the coupling portions 19, 20 may snap into the respective recesses. Reference may be had to the copending application Ser. No. 480,698 of Rabe et al., filed Aug. 18, 1965, and assigned to the same assignee.

The main body portion of the holder means 14 further comprises two upwardly extending distancing projections or ribs 21, 22 which engage the internal surface of the cover 11 to maintain the latter at a desired distance from the windings of the transformer 9. A side wall 23 of the holder means 14 extends forwardly below the opening 10 and is outwardly adjacent to the electrode 7 This side wall 23 extends between the sheath 17 and the adjoining side panel of the cover 11. A similar side wall may be provided between the sheath 18 and the other side panel of the cover 11. The purpose of the side wall or side walls 23 is to protect the spark gap and to prevent a spark from jumping between the respective electrode and the metallic material of the cover 11.

The opening 10 in the top panel of the cover 11 is preferably dimensioned in such a way that the ame produced on ignition of a fuel jet passing along the spark gap between the electrodes 7, 8 can propagate itself outwardly to the upper side of the cover 11 but cannot backfire into the interior of the cover. This protects the transformer 9, the sheaths 17, 18 `and the main body portion of the holder means 14 against overheating.

As stated before, the holder means 14 preferably consists of a casting resin which is a satisfactory insulator for electric current. For example, the holder means may consist of an epoxy resin. In producing the holder means, the transformer 9 and the electrodes 7, 8 are electrically connected to each other and the resulting assembly is placed into a mold or form which thereupon receives a mass of molten resin. The casting operation is preferably performed in vacuo.

An important advantage of the improved ignition system is that the transformer 9 and the holder means 14 for the electrodes 7, 8 form a rigid structural unit. This simplifies the mounting of such structural unit on or in the carrier 2. The electrical connections 15 between the electrodes and the secondary circuit of the transformer can be established prior to forming of the hol-der means and the latter occupies less space than two separate holders which are normally used in presently known ignition systems for gas lighters to respectively support the transformer and the two electrodes. The material of the holder means 14 may contain suitable filler substances, particularly to improve its strength characteristics, i.e., to insure satisfactory supporting action for the electrodes. This is especially important in certain types of gas lighters which utilize very small electrodes of noble metal and whrein the distance between the exposed tips of the electrodes must be selected and maintained with utmost accuracy. Heretofore, such electrodes were invariably installed in a separate holder which was thereupon mounted in or on the carrier independently of the supporting structure for the transformer. Since the holder means 14 constitutes a very rigid and compact structural element, it can be readily formed with various projections in the form of partitions, tubular extensions, abutments, webs and/or side walls, as well as with depressions, recesses, grooves, channels and the like to facilitate the mounting in the carrier 2, proper spacing from the cover 11, and/or proper retention of electrical conductor or conductors which connect the primary circuit of the transformer with the battery. Also, the holder means 14 may accommodate male or female metallic threaded elements to facilitate mechanical and/or electrical connection with the remaining lighter elements. For example, and in addition to the projections 16, 19, 20, 21, 22, 23 which are shown in FIGS. 1 and 2, the holder means 14 may comprise pins to support a microswitch. The aforementioned side Wall or side walls 23 of the holder means 14 allow for placing of the electrodes very close to the side panels of the cover 11 without the danger of sparking. Also, such side walls can enclose the actual ignition zone to insure satisfactory ignition, especially when the lighter is operated several times in rapid succession. The sheaths 17, 18 preferably extend well into the main body portion of the holder means. This insures that, save for the tips of the electrodes 7, 8, the entire secondary circuit and the major portions of the electrodes are fully embedded in insulating material which is contrary to the construction of presently known lighters wherein the connection between the electrodes and the high-voltage leads of the transformer is established by separate conductors in the form of wires.

Such nearly complete insulation of the electrodes and of the secondary circuit allows for placing of the electrodes very close to each other, i.e., much closer than in heretofore known ignition systems for gas burners. The sheaths 17, 18 may but need not be rigid. Regardless of the rigidity or exibility of such sheaths, the aforementioned projection 16 of the main body portion of the holder means 14 provides a highly satisfactory rigid support for the two electrodes. The projection 16 can extend close to the actual spark gap and may accommodate the major parts of the sheath 17 and 18.

FIG. 3 illustrates different holder means 24 for two electrodes 25, 26. The main body portion of this holder means 24, fully or nearly fully surrounds the transformer and the holder means comprises two sheaths 27, 28 which surround the electrodes 25, 26 and are integral with the main body portion. In other words, the entire holder means 24 forms a single rigid element which surrounds the transformer and supports the two electrodes. This embodiment of my invention provides an exceptionally stiff support, both for the transformer and for the two electrodes.

The main body portion of the holder means 24 comprises laterally extending coupling portions 29 which can snap into complementary recesses of a carrier corresponding to the carrier -2 of FIG. l. The upwardly extending projections 30 correspond to the distancing projections 21, 22 of FIG. 1. At its underside, the main body portion of the holder means 24 carries a polygonal projection 31 which can serve as a support for a contact spring 32 arranged to engage one pole of the battery.

An important advantage of the construction shown in FIG. 3 is that the sheaths 27, 28 form integral parts of the main body portion of the holder means 24. This simplifies the producton of my ignition system because no separate sheathing must be provided for the electrodes 25 and 26. All that is necessary is to provide satisfactory electrical connections between the secondary of the transformer and the electrodes 25, 26 and eventually between the primary of the transformer and con-ductors which are thereupon connected with the battery. The thus assembled electrical components are placed into a form and the holder means 24 with integral sheaths 27, 28 is formed in a single operation. Such single casting step results in the formation of aforementioned projections 29-31 an-d, if necessary, of suitable recesses, grooves, pins and other appendages or cavities which might be necessary to properly install and connect the holder means 24 in a gas lighter. The number of electrical components is reduced to a minimum if the electrodes 25, 26 are directly connected with the secondary circuit of the transformer, Le., if the electrodes themselves extend into the interior of the main body portion of the holder means 24.

FIG. 4 illustrates certain component parts of a further lighter which is analogous to the lighter of FIGS. 1 and 2. The ignition system comprises a transformer 9 which is at least partially surrounded by the main body portion of a holder means 33 having integral extensions or sheaths 34, 35 accommodating the terminal'portions 36, 37 for two electrodes 38, 39 whose free ends define between themselves a spark gap adjacent to the burner tube 3. The terminal portions 36, 37 are constituted by small tubes into which the respective electrodes 38, 39 extend. The electrodes preferably consist of noble metal, for example, platinum, and may be mechanically clamped in the respective terminals. The inner ends of the terminals 36, 37 are soldered or otherwise electrically connected with the high-tension leads of the transformer 9. A vertical partition 40 of the holder means 33 extends between the extensions 34, 35 toward the burner tube 3 to lengthen the creep distance between the electrodes 38, 39.

The main difference between the ignition Systems of FIGS. 3 and 4 is that the electrodes 38, 39 are not directly connected with the secondary circuit of the transformer 9, i.e., that the system of FIG. 4 utilizes separate terminals 36, 37. Such construction will be resorted to when the material of the electrodes is a noble metal which cannot be properly soldered to the high-voltage leads of the transformer. The electrodes 38, 39 are mechanically connected with the terminals 36, 37 and these terminals are soldered to the high-voltage leads.

As stated before, the holder means of my improved ignition system may consist of a casting resin, particularly an epoxy resin. Such resins are sufficiently stable at temperatures of up to 15G-160 C. This is normally the maximum-permissible temperature for the transformer 9. In order to prevent overheating of the holder means 14, 24 or 33 and/or transformer 9, the opening 10 in the cover 11 is preferably dimensioned in the aforedescribed manner, i.e., so that the flame cannot backfire into the interior of the cover but the jet of fuel will continue to burn outside of the cover. Such dimensioning of the opening 10 allows for placing of the transformer 9` close to the spark gap to reduce the overall dimensions of the lighter. The shield formed by the material surrounding the opening 10 is particularly satisfactory if the cover 11 consists of metallic material which is a good conductor of heat. The short-lasting exposure of the holder means to higher temperatures at the exact moment when the llame is produced on completion of the ignition circuit does no harm because the flame is immediately propagated to the outer side of the cover 11.

The improved ignition system is susceptible of many modifications without departing from the spirit of my invention. For example, the holder means may resemble a substantially flat plate which is directly connected with the transformer 9. A satisfactory rigid connection between the holder means and the transformer can be established even if the transfomer is detachable from such holder means. For example, a rigid connection may be established by sockets which are provided on the transformer and can be mechanically connected with the terminals of electrodes or directly with the electrodes. Furthermore, the various projections and/ or recesses in the holder means may be obtained by machining after the holder means is formed in a mold. Also, such projections may be constituted by inserts which are placed into the mold prior to pouring of the material which, when allowed to set, forms the holder means.

Without furt-her analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specic aspects of my contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is:

1. An electrical ignition system for use in gas lighters, comprising a burner arranged to discharge combustible gas; a source of electrical energy; transformer means conductively connected with said source of electrical energy and having a high-voltage circuit; a pair of electrodes electrically connected in said circuit and defining between themselves a spark gap so positioned with reference to said burner that gas discharged from the latter is ignited when said electrodes produce a spark across said spark gap; means for establishing and interrupting said circuit at will of a user; and insulating holder means carrying said electrodes, said insulating holder means and said transformer means being lirmly secured to each other, forming a single unit together with said pair of electrodes carried by said insulating holder means, so that after mounting of said unit in a gas lighter said insulating holder means maintains said electrodes immovably in predetermined position with reference to each other and to said burner.

2. An ignition system as dened in claim 1, wherein said holder means surrounds at least a portion of and is rigid with said transformer means.

3. An ignition system as defined in claim 1, wherein said holder means consists of a casting resin.

4. An ignition system as defined in claim 1, further comprising a carrier for said holder means, said holder means comprising at least one coupling portion engageable with said carrier.

5. An ignition system as defined in claim 1, wherein said holder means comprises at least one coupling portion engageable with an element of the structure in which the ignition system is put to use.

6. An ignition system as defined in claim 1, wherein said holder means comprises at least one side wall outwardly adjacent to one of said electrodes.

7. An ignition system as defined in claim 1, wherein said holder means comprises partitioning means extending between said electrodes.

8. An ignition system as defined in claim 1, wherein said holder means comprises a main body portion surrounding at least a portion of said transformer means and sheaths surrounding said electrodes and rigid with said main body portion.

9. An ignition system as defined in claim 8, wherein said sheaths are rigid.

10. An ignition system as defined in claim 8, wherein said sheaths are integral with said main body portion.

11. An ignition system as defined in claim 1, further comprising a cover member having an opening for said gas, said opening being so dimesioned that the fiame produced on ignition of said gas by said electrodes can propagate itself through the opening and outwardly of said cover but is prevented from backfiring into the interior of said cover.

12. An ignition system as defined in claim 1, wherein said -holder means comprises a block-shaped main body portion which surrounds at least the major part of said transformer means and comprises a boss supporting said electrodes.

13. An ignition system as defined in claim 1, wherein said holder means comprises a plurality of projections extending in different directions and adapted to facilitate the mounting of said holder means in the housing of a gas lighter.

14. An ignition system as defined in claim 1, further comprising a metallic cover for said holder means, said holder means comprising at least one distancing projection to maintain said cover at a predetermined distance from the windings of said transformer means.

15. An ignition system as defined in claim 1, said transformer means having a primary and a secondary winding; and further comprising electrode terminal portions provided on said electrodes extending into said holder means and electrically connecting said electrodes directly with said secondary winding of said transformer means.

16. An ignition system as defined in claim 15, wherein said holder means comprises sheaths at least partially surrounding said terminal portions.

References Cited UNITED STATES PATENTS 2,415,979 2/1947 Von Mertens 315-57 X 3,041,562 6/1962 Gammel 264-272 X 3,045,290 7/1962 Anderson et al 264-238 3,147,401 9/1964 WOtring 317-97 3,222,576 12/1965 Thompson 317-97 3,311,789 3/1967 Remy 317-86 V. Y. MAYEWSKY, Primary Examiner.

U.S. Cl. X.R. 

